During the last couple of decades, wheelchairs suitable for action or sports use, such as playing basketball, tennis and other activities, have come into use. The chairs are characterized by their light weight and adjustable wheels. The wheels can be adjusted so that their camber can be changed from 0.degree., that is with the rear, driving wheels located in a vertical plane, to 12.degree., or sometimes more, where the top of the wheel is closer to the chair than the bottom of the wheel. By changing the camber on the drive wheels, height of the front caster wheels also needs to be changed to keep the main pivot axis of the caster wheel vertical.
With conventional sport or action chairs, the camber adjustment takes the user a significant amount of time. Adjusting the camber often requires removing quite a number of parts and adding or subtracting washers to achieve the proper angle. Even when done by a trained technician, the process still takes considerable time. It is a cumbersome, time-consuming job, and requires use of a wrench to torque the nut to proper tightness. During this procedure, in which two washers typically represent 3.degree. of camber, it is easy to lose washers and to mount the wrong number of washers to the mounting bolt, requiring the job to be redone.